Hello. I am making a video project for school and I need to add flags floating above people as they walk and a speech bubble next to a person in one scene. And I need them to move as people in the video move. Is there a way to do that?

Select FLAG graphic, and then in Effects window, use Motion > Scale to shrink down the image to reveal video below. Use Motion tools to size and position flag according to your needs. Keyframes will be needed and can be manually set to move about the screen (animated). Just Google for "Premiere keyframes" and you will find many tutorials on how to do that.

If you have Photoshop or other graphics program that can save a graphic with "alpha channel", which is a transparent background, such as .psd or .png, this may be helpful for the flag and text bubbles. Save with transparency and then simply overlay above video, no scaling/cropping needed to reveal video under it.